Teaching practices and rationales of experienced online social studies teachers at one fully online high school in the southeastern United States were aligned with the Community of Inquiry theoretical framework using the descriptive case study method. The practices and beliefs of three male teachers and one female teacher, all with three or more years of experience in the online classroom, were studied using interviews, observations, and document analysis. Results led to an adaptation of the Community of Inquiry framework to the K-12 setting entitled the K-12 Community of Inquiry framework. Further research is needed to identify practices of K-12 fully online teachers for all subject areas and to verify the applicability of the K-12 Community of Inquiry framework.